My last essay dealt with my confusion when reading a recent review (Schurger et al 2015), in which the authors didn't define what they meant by ‘spontaneous’ and I then interpreted the term ‘spontaneous voluntary’ as a near-oxymoron. Although this problem appeared mainly because the authors didn't define their terms, and not from inherently oxymoronic qualities of the phrase itself, this confusion was waiting to happen, because there is no good term to properly describe what participants do in many experiments in the field of volition.
In our experiments, we ask participants to do something ostensibly odd: press a button whenever you want (within two to twenty seconds, depending on experiment), but don’t plan ahead of time when you will do so. The action therefore isn't triggered by any direct external stimulation and it is also voluntary in that the participants aren't forced to press the button. Schurger et al (2015) called these ‘spontaneous voluntary movements’, which they abbreviated with SVMs; others have called them ‘internally-triggered’ actions.
To be honest, I don’t really like either term: ‘spontaneous voluntary movement’ (SVM) is awfully long and acronyms are almost always to be avoided because they can easily interfere with others (if you use brain decoding, a typical technique is the support-vector machine, aka SVM); similarly, ‘internally-triggered actions’ is just a bit clunky.
Therefore, I introduce a new word to eliminate the problems with the existing expressions:
Spoluntary (adj.): something that has no direct external cause and is voluntary; a portmanteau of ‘spontaneous voluntary’ to replace both that term and ‘internally-triggered’. Pronounced like ‘voluntary’, but with a ‘sp’ instead of a ‘v’. Spoluntary could also appear as an adverb (spoluntarily) or as a noun (spoluntarity).
Admittedly, it isn't exceptionally elegant either, but I’d say it’s still preferable to the other two terms currently used: it’s shorter, unambiguous, and doesn't rely on acronyms.
Schurger, A., Mylopoulos, M., & Rosenthal, D. (2016). Neural antecedents of spontaneous voluntary movement: a new perspective. Trends in Cognitive Science, 20 (2), 77-79.